Retirement Benefits and Trusteed Assets Retirement Benefits and Trusteed Assets (Details Textuals) (USD $)	9 Months Ended			3 Months Ended		9 Months Ended				3 Months Ended		9 Months Ended		3 Months Ended			9 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Other Postretirement Benefit Plan, Defined Benefit [Member]	Sep. 30, 2012 Other Postretirement Benefit Plan, Defined Benefit [Member]	Sep. 30, 2013 Other Postretirement Benefit Plan, Defined Benefit [Member]	Sep. 30, 2012 Other Postretirement Benefit Plan, Defined Benefit [Member]	Jun. 30, 2013 Other Postretirement Benefit Plan, Defined Benefit [Member]	Dec. 31, 2012 Other Postretirement Benefit Plan, Defined Benefit [Member]	Sep. 30, 2013 Pension Plan, Defined Benefit [Member]	Sep. 30, 2012 Pension Plan, Defined Benefit [Member]	Sep. 30, 2013 Pension Plan, Defined Benefit [Member]	Sep. 30, 2012 Pension Plan, Defined Benefit [Member]	Sep. 30, 2013 Common Stock [Member] Pension Plan, Defined Benefit [Member]	Jun. 30, 2013 Common Stock [Member] Pension Plan, Defined Benefit [Member]	Mar. 31, 2013 Common Stock [Member] Pension Plan, Defined Benefit [Member]	Sep. 30, 2013 Common Stock [Member] Pension Plan, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Service Cost				$ 9,000,000	$ 15,000,000	$ 37,000,000	$ 51,000,000			$ 22,000,000	$ 20,000,000	$ 71,000,000	$ 61,000,000
Pension Contributions												250,000,000		100,000,000	50,000,000	50,000,000	200,000,000
Estimated Future Employer Contributions in Current Fiscal Year						120,000,000						25,000,000
Contributions by Employer						145,000,000
Retiree Health Care Allowance	3,250
Assumptions Used Calculating Benefit Obligation, Discount Rate								4.30%	4.15%
Remeasurement Reduction to Post Retirement Benefit Obligation		258,000,000	439,000,000
Remeasurement Reduction to Post Retirement Benefit Obligation Liability		721,000,000	1,200,000,000
Remeasurement Decrease in Benefit Cost for Postretirement Plans		69,000,000
Annual Decrease in Other Postretirement Benefits Costs due to Remeasurement	$ 40,000,000